FIG. 7 and FIG. 8 are sectional views of an essential part of a conventional portable electronic device, portable phone 280 disclosed in Japanese Patent Laid-Open Publication No. 2003-37890 and Japanese Patent Laid-Open Publication No. 11-25946. Portable phone 280 includes loudspeaker 35, circuit component 40 having electronic component 50 mounted thereto, display module 60, such as a liquid crystal display, and case 70 for storing them. Spring terminal 230 is formed by folding a single sheet-like elastic metal plate having conductivity, and one end 230C of spring terminal 230 is mounted to the loudspeaker. Spring terminal 230 extending from loudspeaker 35 receives a pressure from circuit component 40, contacts a power supply section of circuit component 40 at an appropriate spring pressure, and supplies power to activate loudspeaker 35.
The other end of spring terminal 230 is folded toward loudspeaker 35 to form folded section 230A, so to prevent spring terminal 230 from elastically deforming and contacting loudspeaker 35 over a reversible deformation limit of elastic deformation of the metal plate. Folded section 230A regulates a range within which spring terminal 230 of the metal plate can be folded, and restricts the distance between the other end 230B of spring terminal 230 and loudspeaker 35 so that the distance is longer than a predetermined value.
Portable electronic devices, such as portable phone 280, game machines, or navigation systems, have recently had small sizes, and the market thereof has grown. Accordingly, portable electronic devices may be handled roughly. Upon being dropped accidentally, being carried in a bag, or receiving an impact force while it is left in an automobile, portable electronic devices may be significantly damaged unintentionally.
FIG. 8 is a sectional view of spring terminal 230 of portable phone 280 shown in FIG. 7 which has received an excessive impact due to an external factor, such as a drop impact and is thus deformed to a smaller thickness. Spring terminal 230 is pressed to circuit component 40 to deform, and folded section 230A deforms and is crushed. In this case, spring terminal 230 deforms over its reversible deformation limit, and does not return to its original shape, thus causing permanent deformation even when the pressure applied from circuit component 40 is eliminated. The spring pressure of spring terminal 230 is decreased. This disables spring terminal 230 to provide a strong spring pressure, accordingly preventing the spring terminal from stably contacting the power supply section of circuit component 40. Upon receiving an impact or vibration, portable phone 280 may produce contact failure between spring terminal 230 and circuit component 40, or may cause a signal to loudspeaker 35 to be interrupted.